1. Field of the Invention
The present invention relates to a ruler used for writing a line or cutting by a cutter, and especially relates to an improvement in a ruler which is contrived such that it can be closely contacted with a surface of an object article such as paper or cloth, and in which there generates no unexpected situation such as positional displacement when using a writing tool or the cutter.
2. Description of the Related Art
From olden times, in the ruler there exist, beside general one for depicting a straight line, various ones such as a triangular ruler used by combining two, a circular ruler, an elliptic ruler, a curved ruler, a T square, a parallel ruler attached to a drawing table, and additionally a template for depicting a letter or a pattern.
This conventional ruler is formed usually by a flat plate of a wood material, a bamboo material, a metal or the like, including a plastic, and made one plane-contacted with a surface of the object article whose line is desired to be drawn and depicted. And, in a case drawing the line by using this ruler, it follows that there is performed by pressing the ruler from above by fingertips of one hand, holding the writing tool with the other hand, and moving a tip of that writing tool along an edge of the ruler.
Here, since the fingertips pressing the ruler are difficult to be extended over a whole of the ruler and they become a form of points, this pressed portion becomes a supporting point, and a pressing by the writing tool in a portion spaced from this supporting point becomes an action point, so that there occurs also such a situation that the ruler is rotated. Strengthening a pressing force in order to prevent this becomes one compelling a feeling of fatigue to a work.
Whereupon, the inventor proposed a ruler in which a positioning of the ruler and a positional movement of the ruler could be smoothly performed by arranging an arch member having a spring property in a surface of the ruler, and protruding downward a slip stop member while interlocking with a pressing of that arch member (refer to Patent Documents 1 and 2).
Patent Document 1: JP-A-2000-79794 Gazette
Patent Document 2: JP-A-2001-162988 Gazette
An issue that the present invention is to solve exists in a point that, although the ruler previously developed by the inventor can certainly suppress the rotation of the ruler at a work time and thus can smoothly perform the positional movement as well, a constituent component number increases, its constitution becomes complicated, manufacturing processes are many, and therefor a cost rises as well.
Additionally, the issues exist in points that when there is made a constitution in which, by using the arch member having the spring property, it is pressed into an opening formed in a ruler main body, there occurs a backlash if there is a slight dimensional difference between the arch member and the opening, and that there is also a fear that, if a biased force is applied to the arch member, there occur a twist and a lateral displacement resulting from the twist.